The sole participant in a trial testing a novel and contentious gene-editing medicine has passed away from undetermined circumstances.

Terry Horgan, a participant from Montour Falls in New York, joined the research in the latter part of August with the hopes of curing Duchenne muscular dystrophy (DMD).

According to Daily Mail, the 27-year-old participant was one of the first Americans to receive CRISPR treatment. CRISPR edits genes by carefully slicing DNA and then letting nature handle the repair.

A mutation in the gene required to make the protein known as dystrophin is the cause of his uncommon hereditary condition that causes muscular atrophy.

The precise reason for Horgan's death last month is yet unknown.

Death in CRISPR Gene Therapy Study Sparks Concern

The latest issue generated concerns about the potential of such treatments generally, which have raised expectations among many families dealing with uncommon and fatal diseases.

"This whole notion that we can do designer genetic therapies is, I would say, uncertain," Arthur Caplan, a medical ethicist at New York University who is not involved in the study, said in an Associated Press (via Voice of America) report.

The nonprofit organization funded the early-stage safety research, which was authorized by the Food and Drug Administration and headed by Dr. Brenda Wong of the University of Massachusetts Chan Medical School.

The goal was to cure Horgan's version of Duchenne muscular dystrophy using the gene-editing technology CRISPR. A mutation in the gene required to create the protein known as dystrophin is the cause of the uncommon, hereditary disorder that causes muscular atrophy. The majority of Duchenne patients pass away due to heart or lung problems.

ALSO READ: Childhood Brain Disease Treatment Revealed in New Study; Scientists Discover the Promising Drug Through Gene-Edited Sheep


It is now unknown if Horgan received the medication and whether CRISPR, other research components, or the illness itself played a role in his passing. Clinical trials, which test new medicines on sometimes-very-ill patients, are not without fatalities.

CRISPR experiments, however, are a recent development. Fyodor Urnov, a CRISPR specialist at the Innovative Genomics Institute at the University of California, Berkeley, said any death during a gene therapy study is a chance for the field to make amends.

Cure Rare Disease's Take

The study's funding organization, Cure Rare Disease, established by Horgan's brother, issued a statement saying: "The loss of Terry is heartbreaking, and he will be remembered as a hero."

The likely reason for Horgan's death is being examined by several research teams around the US, according to Cure Rare Disease, which also noted that the process might take up to four months.

The teams' effort is crucial, according to Cure Rare Disease, which funds the development of 18 additional medicines, to provide light not just on the research results but also on "the challenges of gene therapy generally."

As is necessary for clinical studies, the researchers have submitted a report of the incidence to the Food and Drug Administration (FDA).

The experiment, which was directed by Dr. Brenda Wong, a pediatric neurologist at the University of Massachusetts, was also given agency approval.

Since its initial release in 2012, CRISPR has received both acclaim and criticism.

RELATED ARTICLE: Stem Cells, Gene Editing Used in New Technique to Reveal How Animals Evolve

Check out more news and information on Genetics in Science Times.